On the crystallization of zeolites from waste FCC catalysts

M. R. GONZÁLEZ; PEREYRA, ANDREA M.; E. I. BASALDELLA

Rio de Janeiro

Congreso; 18th International Zeolite Conference; 2016

International Zeolie Association y Brazilian Catalysis Society

Zeolites are used not only as molecular sieves and ion exchangers but also as catalysts due to the presence of acid sites in their structure. Fluid catalytic cracking (FCC) is the most important conversion process used in oil refineries. The components of these active catalysts are crystalline zeolite, aluminosiliceous matrix, binder and kaolin clay as filler. The zeolite used in FCC catalysts is the Y type, whose structure is identified as pertaining to the FAU group, analogous to natural faujasite. The other catalyst components (matrix, binder and filler) are silica and alumina inorganic materials, being kaolin clay the main raw material used for the preparation of the catalyst. Additionally, the spent catalyst also contains small percentages of heavy metals that are incorporated during its use, but the silica and alumina percentages are ca. 100%, so this material constitutes a potential source of starting materials for the synthesis of aluminosilicate zeolites. It is important to reutilize the waste catalysts as well as to synthesize large amounts of zeolite A, which can be used not only as gas desiccant for many industrial processes, among them in the detergent industry. In this work we present the synthesis of zeolite A, using Argentinean waste FCC catalysts as reactants and commercial-grade alumina. The synthesis mechanism is followed through the radial distribution function (Xray diffraction). Additionally, texture evolution is studied by water adsorption. The morphology of the products reaction is observed by scanning electron microscopy (SEM).